1. Field of the Invention
The present invention relates to a small size serial printer for use, for example, small calculator, measuring equipment or electronic translator of pocket size.
2. Description of the Prior Art
Recently, electronic apparatuses provided with printer, for example printer-equipped pocket size calculators, become smaller and smaller. For such small sized electronics apparatuses with printers, there are strong demands to decrease the size of the printer and to decrease the size and power of the power sources. Furthermore, in order to decrease price of the printers, simplicity of the structure and decrease of number of components are also required.
For the abovementioned printers, serial printers of thermal printing type or discharge printing type have been widely used. In such serial printers, printing head is pressed on a recording paper by means of a spring pressure and the head is driven to sweep widthwide of the oblong recording paper for printing, and then at a completion of one line printing the paper is driven or transferred lengthwise. In order to reduce the friction force against the transferring of the paper, it has been general to carry out to remove the printing head away from the paper face. However, for the small sized electronic apparatus, the problem is that the load of transferring the paper and the load of moving away of the head are simultaneously impressed on a small motor, and therefore an extremely small motor can not be used. Furthermore, the conventional apparatus has comprised a considerable number of mechanical components thereby hampering decreasing of the size and thickness of the printer.